Vertical capstan



Nov. 29, 1966 E. BAAS VERTICAL CAPSTAN 5 Sheets-Sheet 1 Filed Nov. 30, 1964 Nov. 29, 1966 E. BAAS 3,:2fi8A3 VERTICAL GAPSTAN Filed Nov. 50, 1964 5 Sheets-$heet 2- mim mg gmu H Nov. 29, 1966 E. BAAS 3,288,438

VERTICAL CAPSTAN Filed Nov. 30, 1964 5 Sheets-Sheet 5 United States Patent 7 Claims. 61. 2s4-1s0 The present invention relates to a vertical capstan with a pawl arrangement for manual actuation in emergencies.

Heretofore known vertical capstans have the drawback that the structural elements intended for manual emergency operation make the entire unit relatively bulky so that the particular advantage of the otherwise rather compact capstan with drive below the deck surface is lost.

It is, therefore, an object of the present invention to provide a vertical capstan, which will overcome the abovementioned drawback.

It is another object of this invention to provide a vertical capstan, which in spite of the provision of a manually operable emergency arrangement will maintain a compact and closed structure.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawing, in which:

FIG. 1 is a vertical section through a capstan according to the present invention.

FIG. 2 represents a horizontal section through the drive and transmission elements arranged below the deck.

FIG. 3 is a horizontal section taken along the line III-III of FIG. 1

FIG. 4 is a partially sectioned top view of the capstan with a pawl-ratchet mechanism.

FIG. 5 is a side view of the arrangement shown in FIG. 4.

The vertical capstan according to the present invention is for manual emergency operation equipped with a pawlratchet mechanism. This pawl-ratchet mechanism comprises a ratchet wheel connected to the capstan shaft for rotation therewith and cooperates with pawls provided in a freely rotatable supporting disc on said capstan shaft. The said pawls are adapted to be actuated by a manually operable lever connectable to said supporting disc. The vertical capstan of the character just described is, according to the present invention, characterized primarily in that the said supporting or bearing disc is mounted on the upper end face of the capstan head in a snugly joining manner and that the said pawls and said ratchet Wheel are encased and mounted in an annular recess between the capstan head and the said bearing disc.

Preferably, the said bearing disc is arranged between the capstan head and a clamping nut selected in conformity with the diameter of the capstan head and screwed onto the end of the capstan shaft. Within said clamping nut, the freely rotatably journalled capstan head covered by a friction lining is adapted to be pressed against a follower disc which is rotatably connected to the capstan shaft.

The capstan according to the present invention thus maintains its appealing shape of a pure body of rotation as it is desired in particular with regard to avoiding accidents.

According to a further feature of the invention, between the said bearing disc and the adjacent clamping nut there is provided an axial antifriction bearing. For purposes of protecting the said antifriction bearing and also the pressure screw, between the clamping nut and the bearing disc there may be provided a labyrinth seal. Also the friction lining provided between the follower disc and the capstan head may be protected in a very simple man- Patented Nov. 29, 1966 ner against sea water and soiling by arranging the said friction lining at the base of the capstan head while providing said capstan head at its lower end with a bellshaped skirt.

Referring now to the drawing in detail, the capstan illustrated therein is equipped with a hydraulic drive which is preferably arranged below the deck. The drive also comprises a transmission housing 1 below the deck which housing also has arranged therein a hydraulic motor 2 operable by oil conveyed through pressure conduits 3 and 4. Hydraulic motor 2 has a drive shaft 5 which through the intervention of a flexible coupling 6 of any standard design is connected with a worm shaft 7. Worm shaft 7 is journalled on one hand in an antifriction bearing 8 supported by one outer wall of housing 1 and is on the other hand journalled in an antifriction bearing 10 supported by a partition 9 of housing 1. In addition to supporting antifriction bearing 10 for worm shaft 7, partition 9 also separates in an oil-tight manner the pressure oil motor 2 proper from the worm drive to be lubricated. Worm 11 mounted on shaft 7 meshes with a worm wheel 12 which is rotatably connected to capstan shaft 13. Housing 1 is provided with openings 14 to permit the operator to watch and serve the structures in housing 1. The said openings 14 are adapted to be closed by a cover. Housing 1 is furthermore provided with an opening 15 for conveying oil into housing 1.

As will be evident from FIG. 1, capstan shaft 13 is at its base within housing 1 arranged below the deck journalled in two antifriction bearings 16 and 17 adapted also to absorb axial forces.

Above the deck surface D there is arranged the foundation plate 18 of the capstan. A follower disc 19 is keyed to capstan shaft 13 and arranged in slightly spaced relationship with regard to said foundation plate 18.

That portion of capstan shaft 13 which protrudes above and beyond disc 19 has provided thereon the capstan head with chain Wheel 20, the capstan drum 21, bearing disc 22 for manual emergency operation, and a clamping nut 23.

As Will be evident from FIG. 1, chain wheel 20 and capstan drum 21 are by means of clamping bolts 24 rotatably connected to each other. Bearing bushings 25 and 26 assure a satisfactory journalling of parts 20 and 21 on capstan shaft 13 and will also assure a good freewheeling after the clamping nut 23 has been loosened as will appear further below.

A ratchet wheel 28 (FIG. 3) is rotatably connected by screw bolts 27 to the upper end face of capstan drum 21. This ratchet wheel 28 cooperates with two pawls 29 which are tiltably journalled in bearing disc 22 by means of screw bolts 30. Leaf springs 31 likewise connected to disc 22 continuously press pawls 29 into their engaging position with regard to ratchet wheel 28. Bushings 32 provided in bearing disc 22 permit the insertion of radial bars, rods, or the like, so that in case of emergency, where a manual actuation is required, it is possible by means of disc 22 and ratchet wheel 28 to turn capstan drum 21 and chain wheel 20. A hearing bushing 33 serves for journalling bearing disc 22 with regard to capstan shaft 13.

That end of capstan shaft 13 which is above and protrudes beyond bearing disc 22 has the form of a clamping screw 34 upon which is screwed the above-mentioned clamping nut 23. An abutment plate 35 connected to the end face of shaft 13 by screw bolts will following the assembly prevent a complete unscrewing of clamping nut 23 so that the working stroke of the latter is limited. A cover cap 36 is provided in clamping nut 23 and above abutment plate 35. An axial bearing 37 is arranged between clamping nut 23 and bearing disc 22. Adjacent said bearing 37 and between the members 22 and 23 there is provided a labyrinth seal 38 which extends over the circumference of parts 22 and 23. Clamping nut 23 may also be provided with bushings to be inserted in bores 39 for receiving radially extending bars, rods, or the like, for manually turning said clamping nut 23.

In order to be able during operation to connect capstan drum 21 and chain wheel 20 to capstan shaft 13 for rotation therewith, it is merely necessary to tighten clamping nut 23 whereby through the intervention of axial bearing 37 the base of the capstan head is pressed against follower drum 19. For purposes of increasing the friction, a friction lining 40 may be provided between follower disc 19 and the base of said capstan head. In the particular embodiment illustrated in the drawing, the friction lining 40 is fixedly connected to chain wheel 20 by means of screws.

The base of the capstan head is at 41 provided with a bell-shaped skirt so that the frictional surfaces between follower disc 19 and friction lining 40 will be protected against the entry of soil and sea water. The circumferential surface of the bell-shaped portion 41 is designed as a ratchet wheel 42 cooperating with pawls 43 shown in FIGS. 4 and 5. Pawls 43 are tiltably journalled by means of a bearing bolt 44 in plate 18. A helical spring 45 interposed between an extension of bearing plate 18 and the front arm of pawl 43 continuously maintains the pawl in engagement with the ratchet wheel 42.

An actuating member 46 arranged at the opposite arm of the pawl serves for disengaging pawl 43. The actuating member 46 (see FIG. is formed by a knurled head screw adapted to be screwed into a corresponding bore 47 of the foundation plate 18 in order to lock pawl 43 in its disengaged position. It will be evident that when clamping nut 23 is in its clamping position, the vertical capstan may in conformity with the supply of oil under pressure through conduits 3 and 4 be turned in a lifting sense and when pawl 43 is in disengaged position be turned in a lowering sense. It is also possible when the hydraulic drive is at a standstill and pawl 43 is in disengaged position, by loosening clamping nut 23 to permit the capstan to turn in its lowering sense under the pull of a rope or an anchor chain. In emergency situations when manual operation is required, the pawlratchet mechanism 28, 29 cooperates with the mechanism 42, 43 in the lifting sense. After the anchor has been lifted, the arrangement can without difficulties be arrested by tightening clamping nut 23 which during the said manual emergency operation is, of course, to be loosened.

It is, of course, to be understood that the present invention is, by no means limited to the particular arrangement shown in the drawing but also comprises any modifications within the scope of the appended claims.

What I claim is:

1. A vertical capstan which includes a rotatable vertical driving shaft having its upper end provided with a thread, a capstan head rotatable about the axis of said shaft and having its upper end spaced from said threaded 'upper end of said shaft, clamping nut means adjustably threadedly engaging said threaded end of said shaft means, first disc means interposed between said clamping nut means and said capstan head and supported by the latter, said first disc means being rotatable about the axis of said shaft and together with said capstan head confining annular closed chamber means, said first disc means being adapted to be manually rotated, pawl and ratchet means arranged in said chamber means, said pawl and ratchet means including a first member formed by a ratchet wheel and also including a second member formed by a pawl, one of said members being operatively connected to said capstan head and the other one of said members being operatively connected to said first disc means, second disc means connected to said shaft means for rotation therewith and being arranged near the lower end face of said capstan head, and friction means interposed between said lower end face of said capstan head and said second disc means, said clamping nut means being operable selectively to be threaded toward and away from said capstan head to thereby respectively establish or interrupt frictional driving engagement between said capstan head and said second disc means and thereby said shaft means through said friction means.

2. An arrangement according to claim 1, in which said friction means is connected to said capstan head.

3. An arrangement according to claim 1, in which said friction means is connected to said second disc means.

4. An arrangement according to claim 1, which includes anti-friction thrust bearing means interposed between said first disc means and said clamping nut means for absorbing axial thrust.

5. An arrangement according to claim 1, in which said first disc means is provided with radial bores for receiving means for manually rotating said first disc means.

6. An arrangement according to claim 1, in which said clamping nut means is provided with radial bores for receiving means for manually rotating said nut means.

7. A vertical capstan which includes a rotatable vertical driving shaft having its upper end provided with a thread, a capstan head rotatable about the axis of said shaft and having its upper end spaced from said threaded upper end of said shaft, clamping nut means adjustably threadedly engaging said threaded end of said shaft means, first disc means interposed between said clamping nut means and said capstan head and supported by the latter, said first disc means being rotatable about the axis of said shaft and together with said capstan head confining annular closed chamber means, said first disc means being adapted to be manually rotated, anti-friction thrust bearing means interposed between said first disc means and said clamping nut means for conveying axial pressure from said clamping nut means to said first disc means when tightening said clamping nut means, labyrinth sealing means likewise interposed between said first disc means and said clamping nut means and surrounding said thrust bearing means, pawl and ratchet means arranged in said chamber means, said pawl and ratchet means including a first member formed by a ratchet wheel and also including a second member formed by a pawl, one of said members being operatively connected to said capstan head and the other one of said members being operatively connected to said first disc means, second disc means connected to said shaft means for rotation therewith and being arranged near the lower end face of said capstan head, and friction means interposed between said lower end face of said capstan head and said second disc means, said clamping nut means being operable selectively to be threaded toward and away from said capstan head to thereby respectively establish or interrupt frictional driving engagement between said capstan head and said second disc means and thereby said shaft means through said friction means.

References Cited by the Examiner UNITED STATES PATENTS 261,530 7/1882 Coffin 254- 1,069,037 7/1913 Sessions. 1,554,634 9/1925 Kersting 254-150 1,653,187 12/1927 Levy 254150 1,735,711 11/1929 Albrecht 254-150 2,288,276 6/1942 Head 254150 X SAMUEL F. COLEMAN, Primary Examiner. 

1. A VERTICAL CAPSTAN WHICH INCLUDES A ROTATABLE VERTICAL DRIVING SHAFT HAVING ITS UPPWR END PROVIDED WITH A THREAD, A CAPSTAN HEAD ROTATABLE ABOUT THE AXIS OF SAID SHAFT AND HAVING ITS UPPER END SPACED FROM SAID THREADED UPPER END OF SAID SHAFT, CLAMPING NUT MEANS ADJUSTABLY THREADEDLY ENGAGING SAID THREADED END OF SAID SHAFT MEANS, FIRST DISC MEANS INTERPOSED BETWEEN SAID CLAMPING NUT MEANS AND SAID CAPSTAN HEAD AND SUPPORTED BY THE LATTER, SAID FIRST DISC MEANS BEING ROTATABLE ABOUT THE AXIS OF SAID SHAFT AND TOGETHER WITH SAID CAPSTAN HEAD CONFINING ANNULAR CLOSED CHAMBER MEANS, SAID FIRST DISC MEANS BEING ADAPTED TO BE MANUALLY ROTATED, PAWL AND RATCHET MEANS ARRANGED IN SAID CHAMBER MEANS, SAID PAWL AND RATCHET MEANS INCLUDING A FIRST MEMBER FORMED BY A RATCHET WHEEL AND ALSO INCLUDING A SECOND MEMBER FORMED BY A PAWL, ONE OF SAID MEMBERS BEING OPERATIVELY CONNECTED TO SAID CAPSTAN HEAD AND THE OTHER ONE OF SAID MEMBERS BEING OPERATIVELY CONNECTED TO SAID FIRST DISC MEANS, SECOND DISC MEANS CONNECTED TO SAID SHAFT MEANS FOR ROTATION THEREWITH AND BEING ARRANGED NEAR THE LOWER END FACE OF SAID CAPSTAN HEAD, AND FRICTION MEANS INTERPOSED BETWEEN SAID LOWER END FACE OF SAID CAPSTAN HEAD AND SAID SECOND DISC MEANS, SAID CLAMPING NUT MEANS BEING OPERABLE SELETIVELY TO BE THREADED TOWARD AND AWAY FROM SAID CAPSTAN HEAD TO THEREBY RESPECTIVELY ESTABLISH OR INTERRUPT FRICTIONAL DRIVING ENGAGEMENT BETWEEN SAID CAPSTAN HEAD AND SAID SECOND DISC MEANS AND THEREBY SAID SHAFT MEANS THROUGH SAID FRICTION MEANS. 